The company, which is part of the current class of Y Combinator-incubated startups, was founded by Matt Harris and Brad Van Vugt. Harris told me that Sendwithus emerged from the pair’s work as developers, when they found themselves repeatedly having to change a bunch of email templates and wanting to test different variants but finding that there was no real technology in place to do so. (Larger companies will usually build their own systems for this, he said.)"